How to check internet access on Android? InetAddress never times out

Question

I got a AsyncTask that is supposed to check the network access to a host name. But the doInBackground() is never timed out. Anyone have a clue?

Answer 1

Kotlin and coroutines

I have placed the function in a ViewModel, which has the viewModelScope. Using an observable LiveData I inform an activity about the connection.

ViewModel

 fun checkInternetConnection() {
        viewModelScope.launch {
            withContext(Dispatchers.IO) {
                try {
                    val timeoutMs = 3000
                    val socket = Socket()
                    val socketAddress = InetSocketAddress("8.8.8.8", 53)

                    socket.connect(socketAddress, timeoutMs)
                    socket.close()

                    withContext(Dispatchers.Main) {
                        _connection.value = true
                    }
                }
                catch(ex: IOException) {
                    withContext(Main) {
                        _connection.value = false
                    }
                }
            }
        }
    }

 private val _connection = MutableLiveData()
 val connection: LiveData = _connection

Activity

 private fun checkInternetConnection() {
     viewModel.connection.observe(this) { hasInternet ->
         if(!hasInternet) {
             //hasn't connection
         }
         else {
            //has connection
         }
     }
  }